I'm new to java and as an introductory assignment on methods, a teacher asked us to create a series of methods involving arrays. He wants a "double" and an "int" for each method. I am struggling getting my linear search method to work because there seems to be an error with my swap method. I am consistantly getting errors on converting my methods from double to int. (I deleted portions of the code that is working ok, so some formatting might be off, I apologize) Any assistance would be greatly appreciated! (knowing java it's probably an obvious mistake)
我是java新手，作为方法的入门作业，老师要求我们创建一系列涉及数组的方法。他希望每种方法都有“双”和“整数”。我正在努力让我的线性搜索方法起作用，因为我的交换方法似乎有错误。我将我的方法从double转换为int时遇到了错误。 （我删除了部分正常工作的代码，因此某些格式可能会关闭，我道歉）任何帮助将不胜感激！ （知道java它可能是一个明显的错误）
ArrayUtils2.java:47: error: incompatible types: possible lossy conversion from double to int
int temp = arr[loc1];
^
ArrayUtils2.java:93: error: no suitable method found for swap(double[],int,double)
swap(arr,ix,small);
public class ArrayUtils2 {
public static void main(String[] args) {
int[] nums = {1,7,5,3,9};
displayArray(nums);
System.out.println();
displayArray(nums);
public static void swap(int[] arr, int loc1, int loc2){
int temp = arr[loc1];
arr[loc1] = arr[loc2];
arr[loc2] = temp;
System.out.println(loc2);
}
public static void swap(double[] arr, int loc1, int loc2){
double temp = arr[loc1];
arr[loc1] = arr[loc2];
arr[loc2] = temp;
}
private static int selectSmallestIndex(int[] arr, int Start){
int smallestValue = arr[Start];
for (int ix = Start; ix < arr.length; ix++){
if (arr[ix] < smallestValue) {
smallestValue = arr[ix];
}
} return smallestValue;
}
private static double selectSmallestIndex(double[] arr, int Start){
double smallestValue = arr[Start];
for (int ix = Start; ix < arr.length; ix++){
if (arr[ix] < smallestValue) {
smallestValue = arr[ix];
}
} return smallestValue;
}
public static void selectionSort(int[] arr){
for(int ix = 0; ix < arr.length; ix++){
int small = selectSmallestIndex(arr,ix);
swap(arr,ix,small);
}
}
public static void selectionSort(double[] arr){
for(int ix = 0; ix < arr.length; ix++){
double small = selectSmallestIndex(arr,ix);
swap(arr,ix,small);
}
}
public static int linearSearch(int[] arr, int num){
for (int ix = 0; ix < arr.length; ix++){
if(arr[ix] == num){
return ix;
}
}return -1;
}
public static double linearSearch(double[] arr, int num){
for (int ix = 0; ix < arr.length; ix++){
if(arr[ix] == num){
return ix;
}
}return -1;
}
}
1 个解决方案
#1
0
You can't convert a double to an int as soon as a double is a floating point data type. You're tring to do int = double which is nonsense.
只要double是浮点数据类型，就不能将double转换为int。你要做int = double这是无稽之谈。
Here is the prototypes of your function : public static void swap(double[] arr, int loc1, int loc2) and the error says you're doing swap(double[], int, double).
这是你的函数的原型：public static void swap（double [] arr，int loc1，int loc2），错误说你正在做swap（double []，int，double）。
#1
0
You can't convert a double to an int as soon as a double is a floating point data type. You're tring to do int = double which is nonsense.
只要double是浮点数据类型，就不能将double转换为int。你要做int = double这是无稽之谈。
Here is the prototypes of your function : public static void swap(double[] arr, int loc1, int loc2) and the error says you're doing swap(double[], int, double).
这是你的函数的原型：public static void swap（double [] arr，int loc1，int loc2），错误说你正在做swap（double []，int，double）。